Community health workers (CHWs) provide essential basic medical care to hundreds of millions of people across the globe. CHWs offer a myriad of services including community sanitation, breast feeding counseling, family planning, management of febrile children, and malaria control and prevention, to name but a few. In fact, CHWs are often the only source of primary health care available to some of the most disadvantaged populations in the world. However, to be effective, CHWs must be trained - and retrained - at regular intervals, and the costs for such trainings can be substantial. In the US, clinicians are required to stay current and maintain their competence through continuing medical education (CME). Increasingly, CME activities are delivered via internet-based, self-teaching modules. A typical example would be a set of topical readings followed by multiple-choice questions, with the answers, and CME credit, provided to the user upon satisfactory completion of the module. This content is typically delivered over the Internet. However, there is no intrinsi reason why this approach could not be adapted so that CME activities are delivered using standard cell phones via SMS text messaging. This would significantly expand professional training opportunities to a far greater range of CHWs than possible through computer/tablet/smart phone platforms, and would be particularly valuable in poorer countries with limited training budgets. In the mCME project, we propose to test the effectiveness and cost effectiveness of a mobile phone-based CME delivery strategy among Vietnamese community-based physician assistants (CBPAs), a cadre of CHW mandated to provide primary health care to rural and disadvantaged populations. We hypothesize that providing CME activities over a mobile platform will significantly improve their professional knowledge, and may also improve their job satisfaction and self- efficacy.